Duct Temperature Sensor Installation 511
21-61-41 Figure 401 Nov 15/68
Page 402
BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.
DUCT OVERHEAT SWITCHES - REMOVAL/INSTALLATION
1. General
A. There are four cabin duct overheat thermal switches. These are a 1900F (880C) and a 2500F (1210C) overheat switch for each control system. The switch installations are similar and are located in the main distribution manifold (Fig. 401). Access to the switches is through the aft bulkhead of the forward cargo compartment.
2. Equipment and Material
A. Controlled Heat Source - Temp Cal probe heater (Attachment to Jet Cal engine analyzer), or equivalent.
B. Jumper Wire
3. Prepare for Removal of Duct Overheat Switch
A. Open OVERHEAT circuit breaker on load control center circuit breaker panel P6-4.
B. Remove center portion of forward cargo compartment aft bulkhead to gain access to main distribution manifold.
4. Remove Duct Overheat Switch
A. Disconnect electrical connector from 2500F (1210C) overheat switch.
B. Cut wire at splice to disconnect from 1900F (880C) overheat switch.
C. Remove screws attaching switch to duct.
D. Remove switch and gasket from duct.
500
May 01/01 BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details. 21-61-51 Page 401
5. Install Duct Overheat Switch
A. Test overheat circuit.
(1)
Connect external electrical power.
(2)
Close OVERHEAT circuit breaker on load control center circuit breaker panel P6-4.
(3)
Push-to-test duct OVERHEAT light for the 1900F (880C) overheat switch or the PACK TRIP OFF light for the 2500F (1210C) overheat switch replacement.
(4)
Install a jumper wire between two pins of electrical connector or between two bared wires and observe that the respective light on the forward overhead panel, both MASTER CAUTION annunciators and the AIR COND annunciator come on.
(5)
Remove jumper wire.
(6)
Push the TRIP RESET switch.
(a) Check that PACK TRIP OFF light and all master caution annunciators go out.
B. Connect electrical connector to 2500F (1210C) overheat switch.
C. Splice wires to make connection to 1900F (880C) overheat switch.
D. Test duct overheat thermal switch operation.
(1)
Apply controlled heat to thermal switch probe and observe that the respective light on the forward overhead panel, both MASTER CAUTION annunciators and the AIR COND annunciator come on.
NOTE: Duct OVERHEAT lights should illuminate at a probe temperature of approximately 1900F (880C) and the PACK TRIP OFF lights at approximately 2500F (880C).
(2)
Remove the heat source.
(3)
Allow sufficient time for the switch probe to cool then push the TRIP RESET switch.
(a) Check that PACK TRIP OFF light and all master caution annunciators go out.
(4)
Determine whether there is any further need for electrical power on airplane. If not, remove external power.
E. Position switch and gasket on duct and install attaching screws.
F. Install center portion of forward cargo compartment aft bulkhead.
500
21-61-51 Page 402 BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details. May 01/01
515 Duct Overheat Switch Installation
Oct 20/85 Figure 401 BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details. 21-61-51 Page 403
CONTROL CABIN TEMPERATURE SENSOR - REMOVAL/INSTALLATION
1. General
A. The control cabin temperature sensor is located behind a screened opening in the ceiling, just forward of the control cabin door approximately four inches left of center (Fig. 401).
2. Remove Control Cabin Temperature Sensor
中國航空網 www.k6050.com
航空翻譯 www.aviation.cn
本文鏈接地址：737 AMM 飛機維護手冊 AIR CONDITIONING 空調(116)
